Since the moment humanity became aware of the irreversible negative impact that the unrestricted consumption of fossil fuels and other nonrenewable energy sources in the construction industry was causing on our planet, the need for developing environmentally sensitive housing and commercial buildings was born.
At the global level, we are facing the so-called World Energy Trilemma, characterized by the increasing difficulty of balancing the concepts of Economy, Energy, and Environment for a given society. On one hand, we demand more and more electric power, to the point one could say that we have become “energyvorous”, demand which in the near future is only expected to keep growing. On the other hand, the production, transportation, transformation and distribution of energy in its best form for human use (electrical power) is very expensive, and at the same time it usually produces a large impact on the environment to which it pertains (from the use of fossil energy—thermal power stations, combined cycle, etc., that prevail today, to the generation of major infrastructure projects for power generation, which impact is not negligible: hydroelectric dams, nuclear power plants and their waste, etc.).
In the United States, buildings are the biggest primary energy consumers, being responsible for more than 40% of the total fossil energy consumed by the nation. The residential and commercial sector is also responsible for almost 35% of the nation's total greenhouse gas emissions. In addition, the substantial amount of natural resources consumed, and the copious amounts of waste generated by the traditional processes of building and demolishing housing and other structures, evince the desirability of creating environmentally sensitive buildings, including for housing.
These facts highlight the relevance of reducing both building energy use and building greenhouse gas emissions as a key to balancing the Energy Trilemma. For this reason, the development of environmentally sensitive buildings has become a trend in the United States and in the world, with particular growth in the last decade.
The challenge of reducing the energy consumption of a building structure resides both in the sustainable generation of the energy it consumes and in the efficiency with which it utilizes such energy. Therefore, energetic independence is closely tied to the energy-efficiency of the Building Envelope, since the energy requirement for heating and/or cooling to keep the interior of the house at a comfortable temperature can be significant, globally accounting for over 35% of all energy consumed in buildings and rising to over 60% in cold climates.
As with every new challenge technology faces, the earlier attempts of developing energetically independent buildings either failed to achieve the desired degree of energy-efficiency or did it at a cost which made them absurdly unaffordable for a regular buyer. In 1996, the “Passivhous Institute” was founded in Germany to establish new standards for buildings pursuing a higher degree of energetic independence, but these houses still had a relatively inefficient performance and a very high cost, besides maintaining a substantial degree of greenhouse gas emissions during its construction and its useful-life. More recently, evolving from the Passivhous, the concept of “Zero-Energy homes” was born.
Zero-Energy homes combine advanced design and superior building systems with energy-efficiency and on-site solar panels to produce as much renewable energy as they consume over the course of a year, leaving the dwellers with a zero-dollar electricity bill, and a Zero-Emissions home. The main advantage of Zero-Energy homes for the home owner is the low cost of utilities, while at a national level it has the great advantage of a much lower environmental impact. Additionally, when implemented at the community level, Zero-Energy homes improve energy security and resilience against power outages and natural disasters.
However, nowadays, the initial investment required to build a Zero-Energy home is high. For the regular consumer, the desire of acquiring sustainable housing (and ideally, a Zero-Energy home) is countered by the much more pressing need of getting affordable housing. Today, the high costs of sustainable buildings make owning a house designed with an environmentally sustainable concept, and particularly one that meets the ambitious standards of being a Zero-Energy home, a luxury that only a few can afford.
Thus, the paramount importance of developing much more affordable Zero-Energy housing and other buildings such as commercial buildings becomes each day more pressing.
The goal of obtaining commercially viable Zero-Energy buildings is of such an importance that major regions of the world are developing policies to move toward them. The ASHRAE Vision 2020 report sets out requirements for enabling them by 2030. Numerous incentive policies, such as investment subsidies, feed-in tariff, net-metering schemes, etc., have been applied to promote the construction of Zero-Energy homes and buildings. Such programs have met with limited success so far for several reasons, one of them being the inherent difficulty of achieving a Building Envelope which is both energy-efficient and cost-efficient. As a result of this difficulty, only a handful of buildings that actually meet the Zero-Energy standard exist in the world, and none of them was built in a carbon-neutral, affordable manner.
Prefabricated homes are generally a good way of achieving affordable housing and reducing the use of natural resources and the greenhouse gas emissions during the construction. However, the current state of the art of prefabricated homes does not provide any options able of achieving the Zero-Energy goal.
For those reasons, we believe that the disclosed invention will provide substantial advancement to the field and become a valuable tool for housing developers, manufacturers and builders, in the quest for obtaining affordable Zero-Energy homes and buildings.